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Axle Example.

449

i

ft

Each bolt supports     ^J of \% W= i'2i \V
= i*2i x7x8^x225 lbs. = 7 tons.

Max. Bra at Bx or B2=Rt x 7" = - x 7 x 7==32§ ton ins.
and     Max. Bm at Bf=->°^-1-3— ~ 49
Bm=/~

25ro/v^

,   ,        49x6

-/=iix5ix5.|==6tonspersq-m-

Example 28.—An axle is loaded as in Fig. 409, with 5 tons at C.
Find greatest Bm; Bjr tending to fracture each journal; and deduce the
diameters at these places, taking/0 = 5 tons. (Hons. Mach. Constr.
Ex. 1879.)

Rtl = ^-x 5=2*14 tons   Rt2= - x 5 = 2-85 tons
Bm at C== 2*14x4 x 12 = 10272 ton inches

.'.   Bm at A = ~ x 10272 =6*42 ton inches

4<>                               -----------------------------------

Bm at B = -~ x 10272 = 8*56 ton inches

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Now in circular beams ~» area goes for bending, and — goes for
shear (seeFig.385, p. 431).